Electrical connection system for an electrochemical analysis system

ABSTRACT

The invention relates to an electrical connection system for an analysis system and a method for analysis of a liquid sample on an analytical test element using the described analysis system. The analysis system comprises an evaluation appliance for evaluation of electrical signals, a test element holder for holding and positioning of an analytical test element in a measurement position, and at least one electrical contact element configured to make electrical contact with at least one electrical contact surface of an analytical test element, and to produce an electrical connection between the contact surface and the evaluation appliance. The at least one contact element is arranged to move to contact the contact surface of a test element held either in a fixed test element holder or a moveable test element holder, such as a slide. Furthermore, the analysis system has a means for moving the electrical contact element to the electrical contact surface of an analytical test element when the test element holder is in the measurement position.

REFERENCE TO RELATED APPLICATIONS

The present application is based on German Patent Application No. DE 102004 060 322.7, filed Dec. 15, 2004 and European Patent Application No.EP 05022049.0, filed Oct. 10, 2005 which are hereby incorporated byreference in their entirety.

TECHNICAL FIELD

The present invention relates to an electrochemical analysis system andmore particularly to an electrical connection system and method forelectrically connecting a test element and an electrochemical evaluationappliance of the analysis system.

BACKGROUND

Analysis systems which allow individual parameters in sample liquids tobe determined have been known for a long time, and many versions of themare commercially available. Particularly for the field of medicaldiagnosis and environmental analysis, appliances are offered which canalso be operated by personnel with less training. Systems such as thesewhich operate without the use of liquid reagents and in which, ingeneral, no preparation of the sample material, or at least no complexpreparation of the sample material, is required, are simple to operate.A “dry chemistry” has been developed for these so-called quick tests, inwhich the liquid contained in the sample liquid is used on its own as asolvent.

By way of example, systems for determination of glucose in the blood arein use, in which the patient places a small amount of blood on a testelement, and carries out the measurement using an appliance which issimple to operate.

Conventional evaluation appliances have an opening, for example a slot,into which a test element can be inserted, typically by hand. Guideelements ensure that a test element is inserted in the intendedorientation. The appliance typically has design features in order toensure the desired positioning of the test element.

There are various forms of test elements. Those known include, forexample, substantially small rectangular sheets, which are also referredto as strips, in whose center a multilayer test area is located.Diagnostic test elements which are in the form of strips are alsoreferred to as test strips. Capillary test elements are known from theprior art, for example from WO 99/29429, for three-dimensionalseparation of a detection zone and a sample application point on a testelement.

A large number of methods are known for measurement of the concentrationof analytes, for example of glucose in a blood sample. Methods such asthese are normally subdivided into one of two categories: opticalmethods or electrochemical methods.

Optical methods are based on color changes which produce an indicationin the course of the verification reaction when the analytes to bedetermined are present. The color change which occurs on the testelement can be detected by reflection-photometry. A transmissionmeasurement is likewise possible, but in some cases necessitates the useof transparent test strips.

Electrochemical methods for determination of the concentration of ananalyte are based, for example, on amperometry or coulometry. Methodssuch as these are known, for example, from the documents U.S. Pat. No.4,654,197, EP 0 505 475 B1, US 2002/0057993 A1, EP 1 321 769 A1, WO03/083469 A2 or U.S. Pat. No. 5,108,564. Electrical signals must betransmitted between the test element and the evaluation appliance inorder to carry out the electrochemical analysis. A test element whichhas been introduced into an evaluation appliance therefore has to haveelectrical contact made with it in the evaluation appliance, with theaid of an electrical connection system.

Test elements which are used in the prior art are generally designed inlayers and have contact surfaces in the form of thin metallic orotherwise conductive layers, in order to make electrical contact. In thecase of evaluation appliances which are commercially available at themoment, the electrical contact elements of the appliance slide over thecontact surfaces during the insertion of the test element, and candamage it in the process. Furthermore, material accumulations occur atthe electrical contact elements of the evaluation appliance. Reliablecontact can therefore not be ensured.

SUMMARY

One object of the present invention is thus to avoid the stateddisadvantages of the prior art and to provide an analysis system havingan electrical connection system for connecting an analytical testelement to an evaluation appliance, and a method for electricalconnection of a contact surface of a test element in an evaluationappliance, which allow reliable contact to be made between the testelement and the evaluation appliance. A further aim is to avoid abrasivedamage to the test element by the electrical contacts of the analysissystem during insertion of the test element into a measurement positionin the analysis system.

According to the invention, this object is achieved by an analysissystem for analysis of a liquid sample on an analytical test element,comprising an evaluation appliance for evaluation of electrical signals,a test element holder configured to hold and position an analytical testelement in a measurement position within the analysis system, and atleast one electrical contact element configured to make electricalcontact with at least one electrical contact surface of an analyticaltest element provided in the test element holder to produce anelectrical connection between the contact surface and the evaluationappliance, wherein the at least one contact element is arranged suchthat it can move relative to the test element holder, and wherein theanalysis system has a means for moving the electrical contact elementinto contact with the electrical contact surface of the analytical testelement when the test element is positioned in the measurement positionin the test element holder.

The object is also achieved by a method for analysis of a liquid sampleon an analytical test element, including the steps of moving theanalytical test element to a measurement position in a test elementholder in an analysis system, and moving a contact element relative tothe test element holder towards a contact surface of the test element inorder to make electrical contact with the analytical test element and inorder to produce an electrical connection between the contact surfaceand the evaluation appliance, and, using the evaluation appliance,evaluating an electrical signal which is transmitted from the testelement via the contact surface and the contact element.

The analysis system according to the invention may, for example, be anappliance for evaluation of glucose in a body fluid, in particular inthe blood. The liquid sample to be analyzed is passed to the testelement which, if appropriate, contains reagents which react withcomponents of the sample. For analysis purposes, this test element ismoved manually or automatically to a measurement position in the testelement holder in the evaluation appliance, before or after the sampleis taken. The measurement position is in this case that position of thetest element in the analysis system in which the electrochemicalanalysis of the sample on the test element takes place.

An electrical contact element makes contact with the test element whenit is arranged in the measurement position for electrochemical analysis.For this purpose, the electrical contact element is moved towards acontact surface on the test element by the means for moving theelectrical contact element, and contacts it, such as by pressing againstit. At least when the test element is positioned in the measurementposition, the contact element is in electrical communication with theevaluation appliance, for example with an electrochemical evaluationcircuit configured to perform the analysis of the liquid sample based atleast partially on the electrical signals transmitted from the testelement. As a result, an electrical connection is produced between atest element in the measurement position and the evaluation appliance.Electrical signals are transmitted via this connection to the evaluationappliance, and are used to determine the glucose content or the contentof some other electrochemically detectable analyte in the sample on thetest element.

By making electrical contact with the test element using the analysissystem according to the invention, and by using the method according tothe invention, the contact element does not touch the contact surface ofthe analytical test element until the test element is positioned in themeasurement position. The separation of the positioning of the testelement and the process of making contact with it helps to prevent thecontact element from grinding or scratching the contact surface. Theelectrode structure of the test element is thus not damaged this way.Since virtually no friction takes place between the at least one contactelement and the at least one contact surface, very small contactsurfaces can be used, thus resulting in a high miniaturizationpotential. The analysis system according to the invention and the methodaccording to the invention also result in less risk of contamination tothe contact element by the sample during removal of the test elementwith the sample from the measurement position after analysis, since thecontact element is separated from the test element again, beforeremoval. When contact is being made with the test element, theelectrical contact element does not press against the contact surfacewith a high contact force until after positioning in the measurementposition, thus ensuring a reliable contact and, if appropriate,additional fixing of the test element by means of the contact element.

According to one embodiment of the present invention, the contactelement is moved at substantially right angles to the contact surface ofan analytical test element which is held in the test element holder.This therefore avoids any parallel movement of the contact element withrespect to the contact surface, and thus damage of the test elementresulting from the contact element sliding over its surface.Furthermore, the contact element can be moved by a rotary movementtowards the contact surface of an analytical test element which is heldin the test element holder. The rotary movement is thus configured toresult in substantially right angles as the contact element is in thevicinity of the contact surface.

A clamping device may be arranged in a test element holder of theevaluation appliance such that the clamping device fixes a test element,which is to be positioned in the measurement position, in the testelement holder.

According to another embodiment of the present invention, a housing isprovided for the analysis system generally or particularly for theevaluation appliance, with the test element holder and/or the means formoving the electrical contact element being arranged such that they orit can move relative to the housing. The contact element can bedisplaced by the means for moving the contact element either by themovement of the test element holder relative to the means for moving, orby movement of the means for moving relative to the housing (with thetest element holder remaining fixed), so that the contact element isultimately moved towards the test element as or after the test elementis positioned in the measurement position. Electrical contact is thusmade with the test element. The analysis system may also contain a drivefor moving the test element holder and/or the means for moving theelectrical contact element, or the test element holder and/or the meansfor moving the electrical contact element can be driven manually.

The analysis system according to the invention may also contain a testelement magazine for holding at least two test elements, and a testelement removal device for automatic removal of a test element from thetest element magazine and for transport of the test element to themeasurement position in the test element holder. Various test elementmagazines are known from the prior art, for example as disclosed in DE198 19 407 and DE 198 54 316 A1, each of which are hereby incorporatedby reference herein. Examples of test element removal devices aredisclosed in EP 0 738 666 B1, DE 197 15 031 A1, U.S. Pat. No. 5,575,403,DE 199 02 601 A1, and DE 43 26 339 A1, which are also herebyincorporated by reference herein.

The invention also relates to an analysis system having an electricalconnection system for connecting an analytical test element to anevaluation appliance, with the test element having at least one contactsurface. The analysis system has a slide which can be moved between aninitial position and an end position in a housing and contains a holdingspace with an inlet opening for holding the test element, with theholding space being bounded by a stop, and at least one contact element(possibly mounted on the slide), which is arranged such that, when theslide is in the initial position, it is at a distance from the contactsurface of a test element which is held in the holding space, and suchthat it is moved from the initial position to the end position towardsthe contact surface by movement of the slide, and is pressed against thecontact surface. The evaluation appliance according to the inventioncomprises an electrochemical evaluation circuit which is electricallyconnected to the contact element, at least in the end position of theslide. In this case, the slide is used as the test element holder.During movement of the slide, a means for moving the electrical contactelement acts on the electrical contact element and moves it towards thecontact surface.

In one embodiment, the test element is pushed into the test elementholder through the inlet opening into the holding space in the slide foranalysis of a liquid sample on a test element, with the slide beinglocated in its initial position. When using a test element in the formof a strip, by way of example, the inlet opening is in the form of anelongated slot. The holding space is a cavity which is formed in theslide and into which the test element can be inserted until it reachesthe stop. When the slide is in the initial position, a contact elementwhich is mounted on it is at a distance from the contact surface of thetest element. When the test element is pushed into the slide, thecontact element does not touch the test element.

As soon as the test element has been inserted into the slide as far asthe stop, the slide is moved away from the initial position to the endposition, by means of the force which is still maintained in theinsertion direction. The test element can be clamped in the holdingspace during the movement of the slide from the initial position to theend position, thus preventing any change in its position relative to theslide. By way of example, the end position of the slide may be definedby a further stop, which limits the movement of the slide. The movementof the slide from the initial position to the end position results inthe contact element being moved towards the contact surface and beingpressed against the contact surface, this resulting in electricalcontact with the test element.

During the movement of the slide from its initial position to its endposition, the test element does not move in the slide with respect tothe slide and the contact element. It remains arranged in the sameposition in the holding space in the slide, resting on the stop.Electrical contact is thus made when the contact element, which ispressed against the test element, is moved with the slide, therebyavoiding the test element sliding over the contact element resulting indamage to the test element or accumulation of material on the contactelement.

The sample which is located on the test element can be analyzedelectrochemically in the end position, which thus comprises themeasurement position. The electrochemical evaluation circuit is used forthis purpose, and is electrically connected to the contact element, atleast when the slide is in the end position. This electrical connectioncan be produced by the movement of the slide to the end position.However, the evaluation circuit can also be continuously electricallyconnected to the contact element.

The electrochemical evaluation circuit is used, for example, forevaluation of measured electrical signals which depend on theconcentration of an analyte on the test element with which contact ismade. Electrochemical evaluation circuits such as these are known fromthe prior art, for example from EP-B1 0505475 or from U.S. Pat. No.5,108,564, which are hereby incorporated by reference herein.

In another embodiment of the present invention, the contact element isarranged recessed in a depression in the slide when the slide is in theinitial position. The recessing of the contact element results in itbeing at a distance from the contact surface of the test element whenthe slide is in the initial position (in particular during insertion ofthe test element into the holding space).

A clamping device may be arranged in the holding space of the slide,such that it fixes a test element, which has been inserted into theslide as far as the stop, in the holding space.

The contact element in one embodiment extends through an opening in theslide, thereby reaching from the holding space within the slide to theoutside of the slide. The contact element is then arranged such that itinteracts with a contact-pressure element on the outside of the slide.In further embodiments, the contact-pressure element has a guide surfacewhich is arranged such that it pushes the contact element into theholding space, towards the contact surface of a test element containedin it while the slide is being moved from its initial position to itsend position. During the movement of the slide from the initial positionto the end position, the guide surface of the contact-pressure elementwhich is arranged outside the slide drives the contact element, whichextends through the opening to the outside of the slide, such that it ispressed into the holding space within the slide until a contact is madewith the contact surface of the test element. In one embodiment, theguide surface is inclined in the direction of insertion and can have acurved surface or comprise a substantially flat plane.

The electrical connections of the electrochemical evaluation circuit inthe evaluation appliance can be connected directly to the contactelement. However, they can also be connected to the contact-pressureelement, which must then be electrically conductive, in order to achieveelectrical contact with the contact surface of the test element uponinteraction with the contact element.

In another embodiment of the present invention, the contact-pressureelement is resiliently flexible and is resiliently deformed when theslide is in the end position, such that it presses the contact elementagainst the contact surface of the test element with an additionalforce. Resilient deformation which is produced by the pressure put onthe contact-pressure element, for example by the bending of the flexiblecontact-pressure element, results in the contact element being subjectedto a force in the opposite direction to the deforming force, pressingthe contact element against the contact surface of the test element.

In yet other embodiments, the contact element itself is resilientlyflexible. The contact element is then deformed resiliently, such as bypressure applied by the contact-pressure element, such that it pressesagainst the contact surface with a force (which if appropriate opposesthe deforming force).

The invention also relates to an electrical connection system in ananalysis system. The electrical connection system has a slide which canbe moved between an initial position and an end position in a housingand contains a holding space with an inlet opening for holding a testelement having at least one contact surface, with the holding spacebeing bounded at least by a stop. The electrical connection system alsohas at least one contact element, which is arranged such that, when theslide is in the initial position, it is at a distance from the contactsurface of a test element which is held in the holding space, and suchthat it is moved from the initial position to the end position towardsthe contact surface by movement of the slide, and is pressed against thecontact surface.

The invention also relates to an analysis system for analysis of ananalyte in a liquid sample, comprising an evaluation appliance whichcontains at least one electrical connection system according to theinvention. The analysis system may also comprise a device for removal ofbody fluid from a body part. A large number of body fluid removaldevices are known from the prior art, for example from WO 01/89383.These are used, for example, to obtain venous blood from the fingertips, or blood or interstitial fluid from other body parts. The bodyfluid obtained in this way is applied to the test element in order to beanalyzed by the analysis system, for example for evaluating its glucosecontent.

In yet other embodiments, the analysis system may have a supplycontainer for test elements and a removal apparatus for automaticremoval of at least one test element from the supply container. Theanalysis system according to this embodiment is an integrated system, bymeans of which the taking of a sample (for example perforation of theskin and application of blood to a test element which has been takenfrom a supply container, has been transported to the sample takingposition and has been positioned there) and sample analysis (for exampletransport and positioning of the test element with the sample in themeasurement position, measurement and evaluation of the relevantvariables, indication of the analysis result) are carried outautomatically.

The invention also relates to an analysis system for analysis of aliquid sample on a test element, comprising a housing, an evaluationappliance for evaluation of electrical signals and at least oneelectrical contact element which is used to make electrical contact withat least one electrical contact surface of an analytical test elementfor enabling an electrical connection to the evaluation appliance. Theevaluation appliance according to the invention also includes a testelement holder which is arranged firmly relative to the housing of theanalysis system. The test element holder thus cannot be moved relativeto the housing. In the analysis system according to this embodiment, theat least one contact element is arranged such that it can move relativeto the test element holder. The analysis system also has means formoving the electrical contact element to the electrical contact surfaceof an analytical test element when it is positioned in the measurementposition in the test element holder.

Also in this embodiment, the means for moving the electrical contactelement is moved manually or automatically (for example by means of anelectric motor) in order to operate the electrical contact element sothat it is moved to the contact surface of the test element.

According to another embodiment of the present invention, the analysissystem has a test element magazine for at least two test elements, and atest element removal device for removal of test elements from the testelement magazine, with the test element removal device having a drive bymeans of which the means for moving the electrical contact element canalso be moved. For example, in the already described removal device fromthe prior art with a plunger, the plunger is driven via a coupling to athreaded rod which is rotated by an electric motor. In the analysissystem according to the invention, the means for moving the contactelement may, for example, likewise be moved via a coupling to thisthreaded rod by means of the electric motor of the removal device. Inthis case, the means for moving the electrical contact element can be arod which can be moved substantially in the longitudinal direction andhas a rod end by means of which the electrical contact element, which isin the form of an electrical toggle lever, can be moved to the contactsurface of a test element which is positioned in the measurementposition in the test element holder. The toggle lever is in this casepreloaded by a spring element such that it is located in a position awayfrom the test element holder until it is operated by the rod end. Duringtest element removal from the test element magazine, the rod is movedparallel to the plunger, and the rod end reaches and operates the togglelever only when the test element that has been removed has reached themeasurement position in the test element holder. The rod end then tiltsthe toggle lever, which is provided as the contact element, so that itmakes electrical contact with the test element, and makes an electricalconnection to the evaluation appliance.

The statements which have been made above with reference to theelectrical connection system according to the invention and the analysissystem according to the invention apply (to the extent that they areapplicable) in the same way to the method according to the invention.

The invention also relates to a method for electrical connection of acontact surface of a test element in an analysis system, having thefollowing steps: inserting the test element into a holding space as faras a stop in a slide which is arranged in a housing such that it can bemoved between an initial position and an end position, with the slidebeing located in the initial position, and a contact element connectedto the slide being at a distance from the contact surface of the testelement when the slide is in the initial position, and moving the slidewith the test element contained in it from the initial position to theend position, with the contact element being moved towards the contactsurface of the test element as a result of such moving, and beingpressed against the contact surface when the slide is in the endposition.

The invention also relates to a method for analysis of a liquid sampleon an analytical test element, including the following steps: moving theanalytical test element to a measurement position in a test elementholder in an evaluation appliance, and moving a contact element relativeto the test element holder towards a contact surface of the test elementwhich is arranged in the measurement position, in order to makeelectrical contact with the analytical test element and in order toproduce an electrical connection to the evaluation appliance, and usingthe evaluation appliance, evaluating an electrical signal which istransmitted from the test element via the contact surface and thecontact element, by the evaluation appliance, wherein the analyticaltest element is moved to the measurement position in a test elementholder which is arranged to be fixed relative to a housing of theevaluation appliance.

These and other features and advantages of the present invention will bemore fully understood from the following detailed description of theinvention taken together with the accompanying claims. It is noted thatthe scope of the claims is definitely by the recitations therein and notby the specific discussion of the features and advantages set forth inthe present description.

BRIEF DESCRIPTION OF THE DRAWINGS

The following detailed description of the embodiments of the presentinvention can be best understood when read in conjunction with thefollowing drawings, where like structure is indicated with likereference numerals and in which:

FIG. 1 shows a schematic illustration of one embodiment of an electricalconnection system, which is contained in an analysis system according tothe present invention, for a test element;

FIGS. 2A to 2C show three steps in the process of making contact with atest element in an electrical connection system as shown in FIG. 1;

FIG. 3 shows a schematic illustration of a second embodiment of anelectrical connection system for an analysis system according to thepresent invention, and the process of making contact with a test elementcontained in it;

FIG. 4 shows a schematic illustration of a third embodiment of anelectrical connection system for an analysis system according to thepresent invention, and the process of making contact with a test elementcontained in it;

FIG. 5 shows a schematic illustration of a fourth embodiment of anelectrical connection system for an analysis system according to thepresent invention, and the process of making contact with a test elementcontained in it;

FIG. 6A shows a fifth embodiment of an analysis system according to thepresent invention; and

FIG. 6B shows a plan view of the analysis system shown in FIG. 6A.

Skilled artisans appreciate that elements in the figures are illustratedfor simplicity and clarity and have not necessarily been drawn to scale.For example, the dimensions of some of the elements in the figure may beexaggerated relative to other elements to help improve understanding ofthe embodiment(s) of the present invention.

In order that the invention may be more readily understood, reference ismade to the following description of embodiments of the invention, whichare intended to illustrate the invention, but not limit the scopethereof.

DETAILED DESCRIPTION

The following description of the preferred embodiment is merelyexemplary in nature and is in no way intended to limit the invention orits application or uses.

FIG. 1 shows one particular embodiment of an electrical connectionsystem which is contained in an analysis system according to the presentinvention, for electrical connection of a test element 6 to anevaluation appliance 55.

A slide 2, such as a test element holder 23 (an example of which isshown in FIG. 6A), is arranged in a housing 1. The slide 2 can be movedin the housing 1, in the movement direction indicated by thedouble-headed arrow 3. An electrical contact element 4 is mounted on theslide 2 and is also moved in the movement direction 3 during movement ofthe slide 2. The slide 2 is illustrated in its initial position inFIG. 1. The slide 2 defines a holding space 5 for holding a test element6. The holding space 5 extends in the slide 2 from the inlet opening 7(which is exemplified in the form of a slot for purposes of receiving astrip-type test element) as far as a stop 8. The test element 6 isinserted into the holding space 5 as far as the stop 8 through theopening 7 with the slide 2 in the initial position. When the slide 2 isin the initial position, the contact element 4 is arranged recessed withrespect to the test element 6, in a depression 9 in the holding space 5.In the initial position, the contact element 4 is thus at a distancefrom the test element 6, and does not touch it. The test element 6 has(on its lower face 10 in FIG. 1) at least one contact surface 16 (shownin FIGS. 3-5), which is arranged directly opposite the contact element 4when the test element 6 has been inserted into the holding space 5 inthe slide 2 as far as the stop 8.

The contact element 4 extends through and is moveably maintained withinan opening 11 in the slide 2. A contact-pressure element 12 is providedon the outside of the slide 2, as the means 24 for moving the contactelement, and interacts with the contact element 4, as will be explainedin more detail in the following text with reference to FIGS. 2A to 2C.

FIGS. 2A to 2C show three steps in the process of making contact withthe at least one contact surface of a test element in the electricalconnection system shown in FIG. 1.

FIG. 2A shows the slide 2 in the initial position in the housing 1. Theslide 2 is in this case located against a first stop 13 in the housing1. The contact element 4 is arranged recessed in the depression 9 in theholding space 5. A test element 6 is inserted into the holding space 5through the inlet opening 7 until it meets the stop 8. During thisprocess, the slide 2 remains in its initial position. The separated(recessed) arrangement of the contact element 4 in the holding space 5prevents the test element 6 from sliding over the contact element 4during insertion into the holding space 5, and prevents damage to thetest element 6 or contamination of the contact element 4, as may occurduring this process in conventional connection systems. Furthermore, thecontact element 4 extends through and is moveably maintained within theopening 11 in the slide 2 to the outside, but is at a distance from thecontact-pressure element 12.

FIG. 2B shows the slide 2 in a position in the housing 1, which isbetween the initial position and the end position. Once the test element6 has been inserted, as is shown in FIG. 2A, as far as the stop 8 intothe slide 2, the slide 2 is moved to its end position together with thetest element 6 in the insertion direction by a continuous manually orautomatically applied force. During this process, the contact element 4interacts with the contact-pressure element 12 in such a way that, assoon as it reaches the contact-pressure element 12, it slides over aguide surface 14, which is in the form of a incline, on thecontact-pressure element 12 and is resultingly displaced through theopening 11 into the holding space 5 to the contact surface of the testelement 6. The contact element 4 is moved at substantially right anglesto the contact surface during this process. In contrast, no relativemovement of the contact element 4 parallel to the surface of the testelement 6, which could result in damage to the surface, is produced, byvirtue of the mounting of the contact element 4 in the slide 2. Duringinsertion of the slide 2, the test element 6 can be fixed by means of aclamping device (not illustrated) in the holding space 5 such that itrests on the stop 8, so that it does not move therein during insertionof the slide 2.

FIG. 2C shows the slide 2 in the end position in the housing 1. The endposition is defined by a second stop 15 for the slide 2 in the housing1, and represents the measurement position for the test element, whichrests on the stop 8 in the holding space 5 in the slide 2. The contactelement 4 is pressed against the contact surface on the lower face 10 ofthe test element 6, so that an electrical contact is produced. Thecontact-pressure element 12 is composed of a resiliently flexiblematerial. It is thus bent downward by the contact element 4, whichpresses against the contact surface 16 of the test element 6, in the endposition as illustrated in FIG. 2C, so that it exerts a correspondingopposing force on the contact element 4 upward (against the contactsurface 16).

Once the analysis of the sample has been carried out with the aid of anelectrochemical evaluation circuit (not illustrated), which is locatedin the evaluation appliance 55, the test element 6 is pulled in thedirection of the initial position of the slide 2. In consequence, theslide 2 is moved together with the test element 6, which is fixed in it,as far as its first stop 13, and the test element 6 is then moved to itsfirst stop 13, and the test element 6 is then pulled out of its holdingspace 5, with the contact element 4 once again being recessed withrespect to the test element 6 in the depression 9, as in FIG. 2A. Theelectrical connection system is once again located in its initialposition, ready for the next contact-making process.

FIG. 3 shows a schematic illustration of a second embodiment of anelectrical connection system in an analysis system according to thepresent invention, for electrical connection of a test element 6 to anevaluation appliance 55.

The electrical connection system has a housing 1 in which a slide 2(test element holder 23) can be moved between an initial position (FIG.3, top) and an end position (FIG. 3, bottom). The slide 2 contains aholding space 5 with an inlet opening 7, in which a test element 6 isheld in FIG. 3. The holding space 5 is bounded by a stop 8. Theelectrical connection system illustrated in FIG. 3 also has anelectrical contact element 4, which is at a distance from the contactsurface 16 of the test element 6 when the slide 2 is in the initialposition (FIG. 3, top). In the initial position, the slide 2 rests on afirst stop 13. The contact element 4 has a plurality of bends and isattached to the housing 1 at one end (and ultimately to anelectrochemical evaluation circuit, now shown), and to the slide 2 atthe other end. During manual or automatic movement of the slide 2 with atest element 6 contained in it from the initial position (FIG. 3, top)to the end position (FIG. 3, bottom), the contact element 4 isresiliently deformed. The resilient deformation is produced by that endof the contact element 4 which is attached to the slide 2 being movedtogether with the slide 2 relative to the housing 1, while the positionof that end which is attached to the housing 1 does not change. As aresult of the resilient deformation of the contact element 4, a sub area17 of the contact element 4 which is arranged close to the contactsurface 16 of the test element 6 is moved towards the contact surface 16and is pressed against the contact surface 16 in the end position of theslide 2, thus producing an electrical contact in the measurementposition. The slide 2 is thus itself used as the means 24 for moving thecontact element 4. In the end position (FIG. 3, bottom), the slide 2rests on a second stop 15. During movement of the slide 2 from the endposition back to the initial position, the movement of the contactelement 4 is reversed, and the electrical contact is disconnected again.

FIG. 4 shows a third embodiment of an electrical connection system in ananalysis system according to the invention, for electrical connection ofa test element 6 to an evaluation appliance 55.

The electrical connection system comprises a housing 1 and a slide 2that can be moved between an initial position (FIG. 4, top) and an endposition (FIG. 4, bottom) (movement direction 3). During this process,the slide 2 is moved from a first stop 13 to a second stop 15. A testelement 6 is arranged in a holding space 5 with an inlet opening 7 and astop 8. An electrical contact element 4, which is mounted such that itcan rotate about an axis 18, is mounted on the slide 2. The test element6 has a contact surface 16. One end 19 of the contact element 4 strikesan electrical contact 20 when the slide 2 is in the end position. Theelectrical contact 20 is used as the means 24 for moving the contactelement, and presses against the end 19 which is configured such thatthe contact element 4 is resultingly moved, by a rotary movement aboutthe axis 18 which causes movement of its other end 21, towards thecontact surface 16 of the test element 6, which is held in themeasurement position in the slide, and makes electrical contact with it.The electrical contact then exists between the contact surface 16 of thetest element 6, the contact element 4 and the contact 20 which, forexample, is connected to the electrical cables 22 of an electrochemicalevaluation circuit (not illustrated) in the evaluation appliance 55.

FIG. 5 shows a fourth embodiment of an electrical connection system inan analysis system according to the invention, for electrical connectionof a test element 6 to an evaluation appliance 55.

A slide 2 is arranged in a housing 1 and can be moved between an initialposition (FIG. 5, top) and an end position (FIG. 5, bottom) between twostops 13, 15. The slide 2 contains a test element 6 in a holding space5, which has an inlet opening 7 and a stop 8. A contact element 4 isfixedly connected to the slide 2, and is set at a distance from thecontact surface 16 of the test element 6 in the initial position. Duringmovement of the slide 2 to the end position (FIG. 5, bottom), thecontact element 4 slides along a contact-pressure element 12, which isconnected to the housing 1. As a result, the contact element 4 isresiliently deformed such that its first end 21 is moved towards thecontact surface 16 of the test element 6, and is pressed against thecontact surface 16 in the end position by means of the contact-pressureelement 12, which is provided as the means 24 for moving the contactelement, so that an electrical contact is produced. When the slide 2 isin the end position, one end 19 of the contact element 4, which projectsbeyond the slide 2, rests on an electrical contact 20. The electricalcontact then exists between the contact surface 16 of the test element6, the contact element 4 and the contact 20 which, for example, isconnected to electrical cables 22 of an electrochemical evaluationcircuit (not illustrated) in the evaluation appliance 55.

FIG. 6A shows a fifth embodiment of an analysis system 50 according tothe invention.

The test element holder 23 in the analysis system is located under anelectrical contact element 4, which is in the form of a toggle lever 25and is used to make electrical contact with at least one electricalcontact surface of an analytical test element 6, and in order to producean electrical connection to an evaluation appliance (not shown in FIG.6A) which is included in the analysis system. The contact element 4 isarranged such that it can move relative to the test element holder 23.The contact element 4 can be moved by a rotary movement about a rotationaxis 26 towards the contact surface of a test element which is arrangedin the measurement position in the test element holder 23.

The test element holder 23 is arranged such that it is fixed relative tothe housing 1, and is fixed to it by means of screws 27. A rod 29, whichcan be moved substantially in the longitudinal direction 28 with respectto the housing 1 and with respect to the test element holder 23, isprovided as the means 24 for moving the electrical contact element 4 andits rod end 30 can operate the toggle lever 25 in order to move thecontact element 4 onto the contact surface of a test element which isarranged in the measurement position. The toggle lever 25 is held by aspring element 31 in the illustrated initial position, in which it is ata distance from the test element holder 23, for as long as it is notmoved by the rod end 30 against the spring force of the spring element31 towards the test element holder 23.

In the analysis system according to the invention as illustrated in FIG.6A, the means 24 for movement of the electrical contact element 4 ismoved automatically by a drive (not illustrated). The drive comprises anelectric motor, which drives a test element removal device 32 forautomatic removal of a test element from a test element magazine 33. Thetest element magazine 33 comprises a container in the form of a drum,which can hold a large number of test elements in individually sealedchambers 34. The test element removal device 32 contains a plunger 35.This plunger 35 is coupled to a threaded rod 37 via a transmissionelement 36. The threaded rod 37 is rotated by the drive (notillustrated) during operation of the test element removal device 32. Thetransmission element 36 converts this rotary movement of the threadedrod 37 to a linear movement in the longitudinal direction 28. Inconsequence, the plunger 35 is likewise moved in the longitudinaldirection 28. In order to remove a test element from the test elementmagazine 33, it is rotated to a position in which the chamber 34 whichcontains the test element to be removed is arranged in front of the testelement holder 23. The plunger 35 is then moved linearly in thelongitudinal direction 28, breaks through the seal on the chamber 34,and pushes the test element out of the chamber 34 into the test elementholder 23.

The rod 29 is likewise moved in the longitudinal direction parallel tothe plunger 35, since it is also coupled to the threaded rod 37, via thetransmission element 36. As soon as the plunger 35 has pushed the testelement that has been removed from the test element magazine 33 and isin the test element holder 23 into the measurement position, the rod end30 reaches the toggle lever 25 and tilts this towards the test element,so that the contact element 4 makes contact with the contact surface ofthe test element. In this position, the contact element 4 produces anelectrical connection between the test element and the evaluationappliance (not illustrated in FIGS. 6A-B), thus allowing anelectrochemical analysis to be carried out on a sample on the testelement.

FIG. 6B shows a plan view of the analysis system shown in FIG. 6A.

This plan view illustrates, in particular, the electrical contactelement 4 (toggle lever 25), the means 24 for moving the contact element4 (rod 29 with the rod end 30), the threaded rod 37, the transmissionelement 36, the plunger 35, the test element magazine 33, the housing 1and the screws 27.

It is noted that terms like “preferably”, “commonly”, and “typically”are not utilized herein to limit the scope of the claimed invention orto imply that certain features are critical, essential, or evenimportant to the structure or function of the claimed invention. Rather,these terms are merely intended to highlight alternative or additionalfeatures that may or may not be utilized in a particular embodiment ofthe present invention.

For the purposes of describing and defining the present invention it isnoted that the term “substantially” is utilized herein to represent theinherent degree of uncertainty that may be attributed to anyquantitative comparison, value, measurement, or other representation.The term “substantially” is also utilized herein to represent the degreeby which a quantitative representation may very from a stated referencewithout resulting in a change in the basic function of the subjectmatter at issue.

Having described the invention in detail and by reference to specificembodiments thereof, it will be apparent that modification andvariations are possible without departing from the scope of theinvention defined in the appended claims. More specifically, althoughsome aspects of the present invention may be identified herein aspreferred or particularly advantageous, it is contemplated that thepresent invention is not necessarily limed to these preferred aspects ofthe invention.

1. An analysis system for analysis of a liquid sample on an analyticaltest element, comprising an evaluation appliance for evaluation ofelectrical signals, a test element holder configured to hold andposition an analytical test element in a measurement position within theanalysis system, and at least one electrical contact element configuredto make electrical contact with at least one electrical contact surfaceof an analytical test element provided in the test element holder toproduce an electrical connection between the contact surface and theevaluation appliance, wherein the at least one contact element isarranged such that it can move relative to the test element holder, andwherein the analysis system has a means for moving the electricalcontact element into contact with the contact surface when the testelement is positioned in the measurement position in the test elementholder.
 2. The analysis system of claim 1, wherein the contact elementis moveable at substantially right angles to the contact surface.
 3. Theanalysis system of claim 2, wherein the means for moving the contactelement comprises rotary movement of the contact element towards thecontact surface.
 4. The analysis system of claim 1, further comprising ahousing, the test element holder and the contact element being providedin said housing, and the test element holder being moveable relative tothe housing.
 5. The analysis system of claim 4, the test element holderand the contact element comprising an electrical connection system forproducing an electrical connection between the evaluation appliance anda test element held within the test element holder, the test elementholder comprising a slide that is moveable between an initial positionand an end position within the housing, the end position comprising themeasurement position, the slide defining a holding space bounded by astop and configured to receive a test element through an inlet openingin the slide, wherein the electrical connection system is configuredsuch that the contact element is set at a distance from the contactsurface of the test element when the test element is held in the holdingspace and the slide is in the initial position, and such that the meansfor moving the contact element causes the contact element to be pressedagainst the contact surface when the slide is in the end position inorder to produce and electrical connection between the contact surfaceand the evaluation appliance.
 6. The analysis system of claim 5, thecontact element being at least partially mounted on the slide.
 7. Theanalysis system of claim 6, the contact element being mounted on theslide and recessed relative to the test element in a depression in theholding space when the slide is in the initial position.
 8. The analysissystem of claim 7, the contact element extending through and beingmoveably maintained within an opening in the slide, the means for movingthe contact element comprising a contact-pressure element fixedlymounted within the housing and outside the slide.
 9. The analysis systemof claim 8, the contact-pressure element having a guide surfaceconfigured to displace the contact element into the holding space towardthe contact surface as the slide is moved from the initial position tothe end position.
 10. The analysis system of claim 9, thecontact-pressure element comprising an inclined plane configured toguide the contact element as the slide is moved from the initialposition to the end position.
 11. The analysis system of claim 8, thecontact-pressure element comprising an electrically conductive materialand being in electrical communication with the evaluation appliance. 12.The analysis system of claim 6, the contact element also being partiallyfixedly mounted on the housing and being resiliently flexible andconfigured such that movement of the slide from the initial position tothe end position resiliently deforms the contact element into contactwith the contact surface.
 13. The analysis system of claim 6, thecontact element also being resiliently flexible and comprising one endthat contacts an electrical contact in electrical communication with theevaluation appliance when the slide is in the end position, and an otherend that is resiliently deformed toward the contact surface when theslide is in the end position by a contact-pressure element fixedlymounted to the housing, the contact-pressure element comprising themeans for moving the contact element.
 14. The analysis system of claim6, the contact element being rotatably mounted to the slide, the meansfor moving the contact element comprising an electrical contact inelectrical communication with the evaluation appliance, the contactelement comprising one end that contacts the electrical contact when theslide is in the end position and which contacting causes an other end ofthe contact element to rotate towards the contact surface.
 15. Theanalysis system of claim 1, further comprising a housing, the testelement holder and the contact element being provided with the housing,and the test element holder being fixed relative to the housing.
 16. Theanalysis system of claim 15, further comprising a test element magazinefor holding at least two test elements, and a test element removaldevice for removal of a test element from the test element magazine andfor transport of the test element to the measurement position in thetest element holder.
 17. The analysis system of claim 16, the testelement removal device comprising a drive operatively connected to themeans for movement of the contact element.
 18. The analysis system ofclaim 16, wherein the contact element comprises a toggle lever, and themeans for moving the contact element comprises a rod moveable in thesubstantially longitudinal direction and having a rod end by means ofwhich the contact element can be moved to the contact surface of a testelement which is positioned in the measurement position in the testelement holder.
 19. The analysis system of claim 1, wherein theevaluation appliance comprises an electrochemical evaluation circuitconfigured to perform analysis of the liquid sample on the test elementbased at least partially on the electrical signals transmitted from thetest element.
 20. A method for analysis of a liquid sample on ananalytical test element, comprising the steps of: moving the analyticaltest element to a measurement position in a test element holder in ananalysis system; moving a contact element relative to the test elementholder towards a contact surface of the test element in order to makeelectrical contact with the analytical test element and in order toproduce an electrical connection between the contact surface and anevaluation appliance; and, using the evaluation appliance, evaluating anelectrical signal which is transmitted from the test element via thecontact surface and the contact element.
 21. The method of claim 20,wherein the test element holder is fixed relative to a housing forcontaining the analysis system.
 22. A method for electrical connectionof a contact surface of a test element in an evaluation appliance for ananalysis system, comprising the steps of: inserting the test elementinto a holding space as far as a stop in a slide which is arranged in ahousing, the slide being moveable between an initial position and an endposition, the slide being located in the initial position at theinserting step and a contact element being provided in the evaluationappliance and set at a distance from the contact surface when the slideis in the initial position; and moving the slide with the test elementcontained in it from the initial position into the end position, withthe contact element being moved towards the contact surface of the testelement and pressed against the contact surface when the slide is movedinto the end position.